Google's websites continued to be the US's most-used search source in July, but lost 1 per cent market share to Yahoo, says comScore Networks Inc.

Google accounted for 43.7 per cent of all US searches, but declined in total use for the first time after 11 consecutive months of increases, comScore said. Yahoo's sites increased to 28.8 per cent, up 0.3 per cent over June of this year, but still down by 1.7 per cent compared to the same month last year. Microsoft and MSN sites stayed unchanged at 12.8 per cent.

Yahoo and Google continued to dominate the browser-based toolbar search market, with over 95 per cent of all toolbar searches between them, comScore said.

All searches totalled 6.3 billion for July, down 2 per cent from June and reflecting seasonal change, comScore said.